Power shovel



March 30 ,v 1926.

' 1,578,702 E." J. ARMSTRONG POWER sHovEL Filed April 5, 1924 2 Sheets-Sheet 1 l dl l h March 30; 1926.

E. J. ARMSTRONG POWER SHOVEL Filed April 5. 1924 2 Sheets-Sheet 2 ti'on;,willi.appeamfromzthez specification; aud t-a1 @of; Pennsylvania;- haveniinyentednewrwandi;

Ellwmj; LASSIGHOB: T01? ERIE 'ISTEA MK SHOVEL CW1},'OEMEWQPENNSWANIAQ .Af;{1C0RBQRATIO.Ni \OI JPENNSILVANIA.

useiulilmprovementstin:Powen- S hovels,1 .o; which-:th'effollowing isia specification A In handling; ,po wer-.=ishotvels, tp-partlcularlyi those. drivemfromaa tmotorr m011ntedt'on tl ie iplatform; difiiculty:has;beemgexpenenced in).

driving;thesshipper;Vshait'f controlling.- f the .7

SeveraLl expedi.

of the boom; on which fthez shipper Shaitjis I usually-mountediwithoutgiadjustlngathegdrive ing connection: a The present: lnvention -1s 4 ,n

,3 designedvto" permitziof; the. use t ot a a driving;

chain: foreconve ingsithe;.-movement from: the i power; onsthe p atformvatozthe; shipper, shaft; andguidin'g. the-samejso;assto-lpermitsof the swingingqo stheeb0.0m;Without. theiattentiony;

2:401. adjustment. ofitthe; guidiil'gtrmeans. Ofsthfi a chain. 1.- Featuresas-andgzdetailsiof theainvenw clannsaa- H v The:lnventlonnsnllustrated; 1n1theaoco1nw-panyinggdrawingsease follows-1' l showsza plansyiewlzofz av shovel; ,2 A a .sideI-e1evation: of: the, same; is,

guidmgmeansm l markslithez shslvela platform the; truck: on: which; it 's imounted; ,3 a the; shovel boom, thisibeingplvotedtatg 3*; on:- the' platform; 4 Y

ing; the. track; .x,andzi- 8 bearingst on i the a boom; in ;whith'itheshafita'lisajournaledt A dippen 9 is iarrangedomthmstxck: A hoisting; line; 10, runs;..,-ov:er a .;sheavea 1 11i and: through 'a sheavevlzi'om hejdippertandz is driven? from a adrum;13iiomtherplatformzinz the. usual: man- 'isprockettl8.zon,\theiplatiofmia A. IIlQtOln 19;; iismounteditonithe p1 attorm: It; has; a" po vven: pulley; 20.51, I A belt; 21'? con-,: 7

VBYSK'PQWQIF- fnomrtheo pulley to a pulley 222.12 AC-reversingztdeiricezzfon llandlingdhe *dippert: is pnoyided; {a

shafts'a-23tand; 26: The1gears.29and 30 mesh; with a gear;- 31 fixed-;.. on a shaft 32. The-sprockehl8?;is: fixedon the shaft 32.. By throwing the; clutches the: gear? 31% may be vdriveinin ;either;directionzandthus the chain V a-sgearzzi,The]gear.25.'-is;fixedzona. 1;. shaf 1.26. 1 Fluid! actuated; ,clutches .27; and 28larewmounted: on the shafts 23 v and 26 and glockugearsl29'Jand: 30 respectively. with .the

maybeyreversed; as desired-i in; handling the dippert; i

The-sheave 17; isdnounted on a shaft 33 tand the; shafti33iis: mounted in .a bracket ,34;-"thet=b1acket: 34Ebeing secured: to the plat- .form 1; adjacent togzthetpivottflflor bottom .ofxthezboomz; The sheave -l6iis mounted on a shaft 35iandathe & shaft 35.; is carried by an arm: 36'V -pivotally; mounted: on: the: shaft 33. Screw-$ 3,119,122;seouredatostheubracket 34 and extendithrough-a pinw36 in-the arms36 and IlIltS38j8L1f0 providedon the screws by means off which-.1} the iarmamay .be: adj usted, thus swinging-the{sheave-16mmtightem or loosen they-chains;

reaches; of the; chain. with a. guide 5 sheave which-is;.,so. arranged with relation to' the pivotzii and thesprocket'l l that theswinging of."they-boom;.wil15jnot1.--change thewtension on thmchain' s'utficient1y"-to. interfere :with its operation; It 'willEBe'noted-thatthe'line between the taxesioffthe: sheaves crosses a line between the; pivot 3; and i theaxis of the sprocket 14 and? that: .as theu boomi is iswung the sprocket 14 may turn: allowingi the.;chain; to vroll over =;it. so that-swith-the ;-two,. fixeda pointsaat the sheavesa l6 and: 17 the chain? will, be relieved in the two :treachesvtaking up in: one reach and playing outs in the other as the. boom- The. variations within: the :limits is swung; of the swinging oftheboommare very minute, easily withinpth'e workingrequirements' of the chainih; I Theadjustmenteofkthezsheave 16 is along thelin'e of thei-reaxoh between that sheave and the sprocket, 141 and; consequently; does not changee'materially; the relation Y t of the partsa What; I claimwascnew is 1. In. a excavating: machine, the ,combinationofw-a *platform-y a boom pivotally mounted onptheplat-formg ,a shaft mounted on; the boom;- an, excavating device ac Thexproblemiis?to;i talie;care:of;theidouble tuated by the shaft; a driven sprocket fixed on the shaft; a motor on the platform; adriving sprocket driven by the motor; a

chain connecting the driving and driven sprockets; and guide sheaves for each reach of the chain adjacent to the pivot of the boom, said sheaves being I positioned relati vely to the pivoted boom to retain an approximately constant tension on'the chain as the boom is swung.

2. In an excavating machine, the combination of a platform; a boom pivotally mounted on the platform; a shaft mounted on. the boom; an excavating device actuated by the shaft; a driven sprocket fixed on the shaft; a motor on the platform; a driving sprocket driven by the motor; a chain connecting the driving and driven sprockets; guide sheaves for each reach of the chain mounted on the platform adjacent to the pivot of the boom, said sheaves being positioned relatively to the pivoted boom to retain an approximately constant tension on the chain as the boom is swung.

3. In an excavating machine, the combination of a platform; a boom pivotally mounted on the platform; a shaft mounted on the boom; an excavating device actuated by the shaft; a driven sprocket fixed on the shaft; a motor on the platform; a driving sprocket driven by the motor; a chain connecting the driving and driven sprockets; guide sheaves 'for each reach of the chain adjacent to the pivot of the boom, said sheaves being positioned with a line connecting the axes of the sheaves crossing a line from the pivot of the boom to the axis of the driven sprocket.

4:. In an excavating machine, the combination of a platform; a boom pivotally mounted on the platform; a shaft mounted on the boom; an excavating device actuated by the shaft; a driven sprocket fixed on the shaft;-

a motor on the platform; a driving sprocket driven by the motor; a chain connecting the driving and driven sprockets; guide sheaves for each'reach of the chain adjacent to the pivot of the boom, said sheaves being positioned relatively to the pivoted boom to retain an approximately constant tension on the chain as the boom is swung; and means for adjusting one of the sprockets to tension the chain in a direction relatively to the reaches of the chain to maintain equal tension at different positions of the boom.

5. In an excavating machine, the combina tion of a platform; a boom pivotally mounted on the platform; a shaft mounted on the boom; an excavating'device actuated by the shaft; a driven sprocket fixed on the shaft; a motor on the platform; a driving sprocket driven by the motor; a chain connecting the driving and driven sprockets;

guide sheaves for each reach of the chain adjacent to the pivot of the boom, said sheaves being positioned with. a line connecting the axes of the sheaves crossing a line from ,the pivot of the boom to the axis of the driven sprocket; and means for ad-' justing one of the sheaves along the line of" a motor on the platform; a driving sprocket driven by the motor; a chain connecting the driving and driven sprockets; guide sheaves for each reach of the chain; a mounting for the sheaves adjacent to the pivot of the boom comprising a bracket in which one sheave is rotatively' mounted; and an arm rotatively mounted on said bracket on which the other sheave is rotatively mounted, the pivot of the arm being positioned relatively to the reach to swing the sheave mounted thereon along the line of the reach of the chain leading from the sheave to the driven sprocket.

7. In an excavating machine, the combination of a platform a boom pivotally mounted on the platform; a shaft mounted on he boom; an excavating device actuated by the shaft; a driven sprocket fixed on the shaft; a motor on the platform; a driving sprocket driven by the motor; a chain connecting the driving and driven sprockets; guidesheaves for each reach of the chain adjacent to the pivot of the boom; a mounting for the sheaves comprising a bracket; a sheave shaft carried by the bracket on which one of the sheaves is mounted; an arm pivotally mounted on said sheave shaft and on which the other of said sheaves ,is mounted, the arm extending in a direction to swing the sheave mounted thereon along the line of the reach between said sheave and the driven sprocket; and means for adjustingthe arm.

In testimony whereof I have hereunto set my hand.

EDWIN J. ARMSTRONG. 

